Dietary Supplements and the Skin: Focus on Photoprotection and Antioxidant Activity-A Review.

Skin health is not only significantly affected by ageing, but also by other lifestyle-related factors, such as sun exposure, exercise and eating habits, smoking or alcohol intake. It is known that the cutaneous tissue can exhibit visible signs of senescence, in the form of, for example, dull complexion, loss of firmness, or changes in pigmentation. Consumers attempt to improve skin health and appearance not only by cosmetic products, but also with the consumption of food supplements. Recently, there has been an increase in the amount of food supplements with claims that are related to skin and hair health. Nevertheless, the literature is still scarce in evidence of the efficacy of this type of products. Considering this scenario, we aim in this review to assemble studies and methodologies that are directed at the substantiation of the cutaneous health claims of food supplements. For example, we reviewed those that were indicative of antioxidant properties, improvement in pigmentation disorders, increased hydration or protection against the damages caused by ultraviolet radiation.

Is Vitamin D3 Transdermal Formulation Feasible? An Ex Vivo Skin Retention and Permeation.

Vitamin D3 supplementation is important to prevent and treat hypovitaminosis that is a worldwide public health issue. Most types of supplementation are by oral route or fortification foods. The alternative route must be investigated, as transdermal route, for people with fat malabsorption or other diseases that impair the absorption of vitamin D3. This study focused on verifying the feasibleness of vitamin D3 skin retention and permeation with the presence of chemical penetration enhancers (soybean lecithin, isopropyl palmitate, propylene glycol, ethoxydiglycol, and cereal alcohol) at different pharmaceutical forms (gel and cream) through a human skin. The integrity of skin was evaluated by transepidermal water loss (TEWL) during the skin retention and permeation test. The combination of chemical penetration enhancers presented in cream did not compromise the skin, different from the gel that association of cereal alcohol and propylene glycol compromised the skin in 24 h. Gel formulation showed vitamin D3 detection at stratum corneum in 4 h and at epidermis and dermis in 24 h. Vitamin D3 demonstrated an affinity with the vehicle in the cream formulation and was detected at the skin surface. No active was found at receptor fluid for both formulations. In conclusion, the vitamin D3 did not indicate feasibleness for transdermal use probably due to its physical-chemical characteristics such as high lipophilicity since it was not permeated through a human skin. Nevertheless, the transdermal route should be continuously investigated with less lipophilic derivates of vitamin D3 and with different combination of penetration enhancers.